An ectopic pregnancy is an abnormal pregnancy that occurs outside the womb (uterus). The baby cannot survive.
Causes, incidence, and risk factors:
An ectopic pregnancy occurs when the baby starts to develop outside the womb (uterus). The most common site for an ectopic pregnancy is within one of the tubes through which the egg passes from the ovary to the uterus (fallopian tube). However, in rare cases, ectopic pregnancies can occur in the ovary, stomach area, or cervix .
An ectopic pregnancy is usually caused by a condition that blocks or slows the movement of a fertilized egg through the fallopian tube to the uterus. This may be caused by a physical blockage in the tube.
Most cases are a result of scarring caused by:
- Past ectopic pregnancy
- Past infection in the fallopian tubes
- Surgery of the fallopian tubes
Up to 50% of women who have ectopic pregnancies have had swelling (inflammation) of the fallopian tubes (salpingitis) or pelvic inflammatory disease (PID ).
Some ectopic pregnancies can be due to:
In a few cases, the cause is unknown.
Sometimes, a woman will become pregnant after having her tubes tied (tubal sterilization ). Ectopic pregnancies are more likely to occur 2 or more years after the procedure, rather than right after it. In the first year after sterilization, only about 6% of pregnancies will be ectopic, but most pregnancies that occur 2 - 3 years after tubal sterilization will be ectopic.
Women who have had surgery to reverse tubal sterilization in order to become pregnant also have an increased risk of ectopic pregnancy.
Taking hormones, especially estrogen and progesterone (such as those in birth control pills), can slow the normal movement of the fertilized egg through the tubes and lead to ectopic pregnancy.
Women who have in vitro fertilization or who have an intrauterine device (IUD) using progesterone also have an increased risk of ectopic pregnancy.
The "morning after pill" (emergency contraception) has been linked to some cases of ectopic pregnancy.
Ectopic pregnancies occur in 1 in every 40 to 1 in every 100 pregnancies.
Signs and tests:
The health care provider will do a pelvic exam, which may show tenderness in the pelvic area.
Tests that may be done include:
A rise in quantitative HCG levels may help tell a normal (intrauterine) pregnancy from an ectopic pregnancy. Women with high levels should have a vaginal ultrasound to identify a normal pregnancy.
Other tests may be used to confirm the diagnosis, such as:
An ectopic pregnancy may affect the results of a serum progesterone test.
Ectopic pregnancies cannot continue to birth (term). The developing cells must be removed to save the mother's life.
You will need emergency medical help if the area of the ectopic pregnancy breaks open (ruptures). Rupture can lead to shock, an emergency condition. Treatment for shock may include:
- Blood transfusion
- Fluids given through a vein
- Keeping warm
- Raising the legs
If there is a rupture, surgery (laparotomy) is done to stop blood loss. This surgery is also done to:
- Confirm an ectopic pregnancy
- Remove the abnormal pregnancy
- Repair any tissue damage
In some cases, the doctor may have to remove the fallopian tube.
A minilaparotomy and laparoscopy are the most common surgical treatments for an ectopic pregnancy that has not ruptured. If the doctor does not think a rupture will occur, you may be given a medicine called methotrexate and monitored. You may have blood tests and liver function tests.
Most women who have had one ectopic pregnancy are later able to have a normal pregnancy. A repeated ectopic pregnancy may occur in 10 - 20% of women. Some women do not become pregnant again.
The rate of death due to an ectopic pregnancy in the United States has dropped in the last 30 years to less than 0.1%.
The most common complication is rupture with internal bleeding that leads to shock. Death from rupture is rare. Infertility occurs in 10 - 15% of women who have had an ectopic pregnancy.
Calling your health care provider:
If you have symptoms of ectopic pregnancy (especially lower abdominal pain or abnormal vaginal bleeding), call your health care provider. You can have an ectopic pregnancy if you are able to get pregnant (fertile) and are sexually active, even if you use birth control.
Most forms of ectopic pregnancy that occur outside the fallopian tubes are probably not preventable. However, a tubal pregnancy (the most common type of ectopic pregnancy) may be prevented in some cases by avoiding conditions that might scar the fallopian tubes.
The following may reduce your risk:
- Avoiding risk factors for pelvic inflammatory disease (PID) such as having many sexual partners, having sex without a condom, and getting sexually transmitted diseases (STDs)
- Early diagnosis and treatment of STDs
- Early diagnosis and treatment of salpingitis and PID
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